Array Converter: PV AC Module Enabler in Stealth

Eric Wesoff is Editor-at-Large at Greentech Media. Prior to joining GTM, Eric Wesoff founded Sage Marketing Partners in 2000 to provide sales and marketing-consulting services to venture-capital firms and their portfolio companies in the alternative energy and telecommunications sectors. Mr. Wesoff has become a well-known, respected authority and speaker in these fields.

His expertise covers solar power, fuel cells, biofuels and advanced batteries. His strengths are in market research and analysis, business development and due diligence for investors. He frequently consults for energy startups and Silicon Valley's premier venture capitalists.

A few years ago I came across a PowerPoint presentation circulating among the VCs on Sand Hill Road from a PV panel electronics firm with an interesting patent, four unsalaried employees, and no funding.

Fast forward a few years, and Array Converter is in stealth (see note below) while they develop some type of AC panel electronics. They have venture capital funding and an interesting board of directors.

The CEO, Wendy Arienzo, and her staff are not talking to the press. We've heard that their coming-out party is a few months away.

Here's the information we could compile from sources, public and private, as well as from bars and pool halls.

The investors are DFJ, Firelake Capital, Partech International, and Trident Capital. Board members include representatives of those VC firms as well as Solaria's Daniel Shugar and Chairman Kevin Surace of Serious Materials.

Shugar, the CEO of Solaria, told us in email, "Array has some novel things going on with their device that ultimately result in lower LCOE and excellent reliability, and that’s why I am serving on their board." Surace said, "I helped start the company 3 years ago. Balance of system needs a disruptive technology. I believe this has a chance at being that technology."

CEO Arienzo says on her LinkedIn page, "Array Converter converts the DC output of a photovoltaic panel to turbine-quality, 3 phase AC using a simple yet disruptive topology. My vision is to make Array Converter the de facto choice for 3 phase AC solar energy generation."

The former president, now board member of the firm, Kent Kernahan, has a 2008 patent granted for a pulse amplitude modulated current converter (PAMCC), which is part of the secret sauce here.

And it's safe to assume that's what Array Converter is trying to with their direct current to pulse amplitude modulated (“PAM”) current converter. The system consists of distributed power modulators tied into an array controller. The company claims a 25-year warranty. And like all of the previously mentioned companies, Array Converter is entering a market where there is price pressure on every element of the solar lifecycle, from module to installation to electronics. Residential solar inverters have a cost of about $0.45 per watt, utility inverters are in the range of $0.26 and there is pressure to drive those costs down while maintaining performance and reliability. The DOE's Steve Chu wants to see inverters at $0.10 per watt.

So, absent comments from the company, I availed myself to VCs who had passed on the deal and some experts in solar power electronics for their comments. Of course, this is just speculation and educated guesswork on their part.

The original patent concept consisted of interleaving pulses from paralleled PV panels to provide a proper 60 Hz sine wave on the output. There appears to have been some technical issues in executing on that technology, so the shift was made to three-phase.

The question was raised: What happens when rapid shading kills some of the modules in the string? How can you still generate a legal AC sine wave?

The consensus was that this was an extremely clever and unique idea. Just like Solyndra is a clever and unique idea. Solyndra was mentioned by more than one of my contacts as a model of what was happening here. On a positive note, one of the folks i spoke with who is close to the company said that Array Converter has the potential to be a category killer for inverters, and can fundamentally change the way inverters are used, priced, and serviced.